Portable Ubuntu for Windows runs a full-fleshed Linux Ubuntu operating system on your Windows like any other Windows application. Version 3 of this brand runs Ubuntu 9.10 on Windows XP, Vista and Windows 7. Download the latest package that takes about 559MB of your hard disk space (3.81GB when extracted). You can run it directly from your thumb-drive – its so portable.
http://www.kabatology.com/04/03/portabl ... e-windows/